Too small to justify their own blog post but maybe just as useful: This page gathers a few smaller projects and tricks I came across.
For the software side of some ESP8266 development, I bought a cheap ESP01 to USB adapter from AliExpress, expecting a programming adapter. What turned up on my doorstep, however, was just a USB-UART adapter which wasn’t able to drive the reset and GPIO0 pins. Luckily, the missing circuitry could be added easily.More details →
In preparation for being off-grid for a few days, I quickly built this ‘power bank’ around a 12 V 7 Ah lead gel battery. The circuit is simply pushed onto the battery’s 6.3 mm contacts and provides 3 USB ports. Charging circuitry is not included but the battery terminals are still accessible anyway.More details →
While building solenoids, I needed a way to quickly judge the magnetic properties of some unknown steel. A simple analogue hall sensor IC works together with a controlled current source for the coil to drive a XY plotter (or oscilloscope in XY mode) and create simple B–H plots.More details →